a Research and Development Division, Kagome Co., Ltd., 17 Nishitomiyama, Nasushiobara Tochigi, 329-2762, Japan.
Can J Microbiol. 2014 Mar;60(3):139-45. doi: 10.1139/cjm-2013-0774. Epub 2014 Jan 20.
Cell-bound exopolysaccharide (EPS) of the aggregable strain Lactobacillus brevis KB290 isolated from traditional Japanese pickles has been reported to protect against the effects of bile. However, there are no reports of bile tolerance mechanisms for other L. brevis strains that have aggregability. To elucidate the mechanism of bile tolerance of L. brevis KB290, we found 8 aggregable L. brevis strains out of 121 L. brevis strains isolated from traditional Japanese fermented pickles. We estimated their growth in artificial digestive juice and the amount of cell-bound EPS. We found 3 types of aggregation for these strains: filiform (<1 mm), medium floc (1-5 mm), or large floc (>5 mm). There was no significant difference in growth between nonaggregable and aggregable strains in the artificial digestive juice. The large floc strains selected from the aggregation strains showed significantly higher growth in the artificial digestive juice than nonaggregable strains. In medium and large floc strains, cell-bound EPS, mainly consisting of glucose, N-acetylglucosamine, and N-acetylmannosamine, were observed. The amount of EPS and each strain's growth index showed a positive correlation. We conclude that aggregable L. brevis strains were also protected by cell-bound EPS.
从传统日本腌菜中分离出的聚集性短乳杆菌 KB290 的细胞结合胞外多糖 (EPS) 已被报道可抵抗胆汁的作用。然而，对于具有聚集性的其他短乳杆菌菌株，尚无关于胆汁耐受机制的报道。为了阐明短乳杆菌 KB290 胆汁耐受的机制，我们从 121 株从传统日本发酵泡菜中分离出的短乳杆菌中发现了 8 株聚集性短乳杆菌。我们估计了它们在人工消化液中的生长和细胞结合 EPS 的量。我们发现这些菌株有 3 种聚集类型：丝状 (<1 毫米)、中絮凝 (1-5 毫米) 或大絮凝 (>5 毫米)。在人工消化液中，非聚集性和聚集性菌株的生长没有显著差异。从聚集菌株中选择的大絮凝菌株在人工消化液中的生长明显高于非聚集性菌株。在中絮凝和大絮凝菌株中，观察到主要由葡萄糖、N-乙酰葡萄糖胺和 N-乙酰甘露糖胺组成的细胞结合 EPS。EPS 的量和每个菌株的生长指数呈正相关。我们得出结论，聚集性短乳杆菌菌株也受到细胞结合 EPS 的保护。
